A man was killed by unknown men while two others including a constable were seriously injured during exchange of firing with dacoits, here on Friday. Police sources said a 37-years-old man was killed in firing of unknown armed men in Peela School area of New Karachi. A cop Faiz Muhammad received bullet injuries in exchange of gunfire with dacoits at Memon Goth in Malir. He was rushed to Liaquat National Hospital. However, 25-years old Roshan, son of Muhammad Siddique, was injured in firing by unidentified criminals.